Monday, December 01, 2008

Is there any sound in the world that holds greater promise than the gentle pop of a cork being pulled from a wine bottle?

It heralds conviviality, conversation, fine food and good cheer. The thin rattle of a metal screw-top cap being removed just isn't the same.

But there is another, far more important reason to insist on a cork.

Every time you weigh up which bottle of wine to buy, you hold in your hands the fate of one of the most important wildlife areas in Europe.

The Montados are the vast cork oak forests of the Alentejo region of southern Portugal. They cover almost a third of that country - an area the size of Wales - and provide 70 per cent of the world's cork products, including 15billion corks a year for wine bottles.

Cork is lightweight, impermeable to liquids, elastic, resilient and chemically inert. It comes from the thick spongy bark of the cork oak. The tree is unique because its bark can be stripped every nine years, a process that actually improves its quality, just as cutting and trimming human hair keeps it healthy.

The bark is still stripped by teams of highly skilled men with axes because no reliable mechanical method has been developed. An average tree, which lives for 170 to 200 years, produces around 4,000 corks per harvest. And each tree can be harvested about 17 times.

This low-impact farming, established at least 300 years ago, helps support an astonishing variety of plant and animal life.

Glossy black storks will nest only in cork oaks, and the trees provide homes for similarly selective booted eagles. Thousands of European cranes arrive in winter to feed on the abundance of acorns.

There are 100 different species of bird, including nightjars, short-toed eagles, azure-winged magpies, bee-eaters, black-shouldered kites and hoopoes.

There are also bats and other small mammals, reptiles and amphibians in the forests.

And the mosaic of cork groves, grassland and scrub provides the perfect habitat for the magnificent Iberian lynx, the world's rarest big cat, which makes the elusive snow leopard look like a champion breeder by comparison.

Only around 100 are thought to remain and the species is on the brink of extinction.

I learnt all this while helping to make a documentary on the Montados for the BBC's Natural History Unit.

Fellow producer Mike Salisbury and I followed a year in the life of Francisco Garrett, whose family has harvested cork for five generations. He told us of the threat to the region.

During the Eighties, EU subsidies encouraged farmers to switch to more intensive crops such as maize, so large areas of cork forest were cleared.

At the same time, wine drinking was becoming more popular, with a corresponding increase in the demand for cork bark.

Producers of cork stoppers could hardly keep pace and in some factories the standards of quality and cleanliness fell.

As a result, complaints of tainted wine rose. This problem is caused by trichloroanisol (TCA), a naturally occurring chemical found on wood and vegetation.

It can also be found on cork stoppers, and if TCA contaminates wine it causes a musty aroma and taste, and we say the wine is corked.

As complaints of corked wine increased, they paved the way for plastic and metal alternatives, marketed as cleaner and more modern.

By 2000 the cork industry had lost almost a quarter of its market to this new competition.

Some landowners, fearing the worst, continued to replace cork oaks with cereal crops. But on the dry impoverished soils in the searing heat of the Montados, many such projects were doomed.

Once felled, cork woodland is very difficult to restore because a complex ecosystem such as the Montados takes knowledge and patience to recreate.

A cork tree cannot be harvested until it is 25 years old, and even then the cork is suitable only for floor tiles. Nor does the second harvest, when the tree is 34 years old, provide the right cork for bottle stoppers.

It is only the third harvest, when the tree is about 43 years old, that it provides the right material.

In other words, cork growers have to invest more than 40 years of management and nurturing before they can collect their first commercial bottle cork harvest.

Francisco told us: 'There's a Portuguese proverb - vineyards of mine, olive groves of my parents, and Montados of my ancestors. That shows the time it takes to have the Montados established.'

International consumption of wine has doubled since 2000, and New World wine firms have continued to promote plastic or screw caps.

Faced with such intense competition, the Portuguese factory owners have modernised their production methods to rid cork of any charge that it may sometimes spoil a bottle of wine.

Nowadays the sheets of raw cork are immersed twice in sealed vats of boiling water, killing off any moulds or bacteria and making the cork more flexible to work with.

Stoppers are individually scanned for imperfections. They are sterilised, polished and graded, and samples from every batch are checked in laboratories for signs of TCA.

The trunks of the cork trees are stripped of bark - but the process is actually good for them

By 2006, the Portuguese cork industry labs seemed to have conquered TCA contamination and bottles of wine using those corks are now hitting our shelves.

Plastic and screw caps will never go away, but biodegradable cork is the only bottle stopper with minimum-impact on the environment during its manufacture. It ticks every 'green' box.

The same cannot be said for plastic stopper production or aluminium screw caps. Although both are recyclable, their production uses a lot of energy, with corresponding levels of greenhouse gas emission.

The cork trees themselves, in contrast, provide a major benefit in absorbing millions of tons of carbon dioxide from the atmosphere.

If the forests disappear, the likely result is that the region will turn into a desert, and the consequences for both man and the wildlife the trees shelter will be significant.

That is why I would like to see retailers provide labelling on the shelves or on bottles, indicating which are stoppered with corks.

Francisco says: 'When we go to the supermarket and choose a wine, I would like to know if the bottle is using a stopper of real cork. Because if it is, I know I am contributing to the sustainability of a vast Mediterranean area where you have a large number of species.

'You can make the choice of preserving a unique habitat. Or not.'

The future of so much wildlife is dependent on this seemingly trivial choice.